When you think about doorbells, does WIFI come to mind? iDoorBell hopes so because they released a WIFI enabled one that allows you to see who is knocking (or ringing) even if your're not at home.
The device includes a camera (of course), a microphone and speaker. When someone rings the bell, you receive a notification on your smartphone where you can see and discuss with the visitor. It doesn't unlock your door yet and costs $165.
You can pre-order now for October delivery on IndieGoGo.